Lesson 3 of 8 · Waves
Experiment⭐ 30 XPReflection, Refraction and Diffraction
Reflection, Refraction and Diffraction.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Nature loves to surprise the careful watcher.
Mind = Blown
🔬 The more you look, the more nature shows you.
Make a hypothesis first
Before you start: write down what you think will happen, and why.
What You'll Learn
Waves reflect off barriers with the angle of incidence equal to the angle of reflection. They refract — change direction — when their speed changes at a boundary. They diffract, spreading out, when they pass through a gap comparable to their wavelength.
Key Words
Tap a word to see its definition.
Materials Needed
- ripple tank
- barriers
- glass plate
- lamp
- water
Safety First
- Keep the lamp and its cable clear of the water.
- Wipe up spills at once.
Steps
Read the explanation above and note the two key terms before you start.
In a ripple tank, place a straight barrier for reflection, a shallow glass plate for refraction, and two barriers forming an adjustable gap for diffraction. Sketch the wavefronts in each case and vary the gap width.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2Diffraction is most pronounced when the gap width is:
Where you see this in real life
This shows up in your everyday life more than you'd think.
Stretch Challenge
Try this in real life this week.
Try one experiment in real life this week — even a tiny one.
For the dinner table
“What's the most surprising thing you learned today?”
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Reflection, Refraction and Diffraction
Run the experiment. Find out what really happens.
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